preacher Abu Abdullah Muhammad ibn Abdullah ibn Ahmad ibn Jabalat quoted Abul Qasim Abdullah ibn Amer al-Ta’ee, on the authority of Ali ibn Musa al-Ridha (MGB), on the authority of Musa ibn Ja’far al-Kadhim (MGB), on the authority of Ja’far ibn Muhammad as-Sadiq (MGB), on the authority of Muhammad ibn Ali al-Baqir (MGB), on the authority of Ali ibn al-Hussein as-Sajjad (MGB), on the authority of al-Husseinibn Ali (MGB), “The Commander of the Faithful Imam Ali (MGB) was in the Jamea Mosque in Kufa. A Syrian man came up to him and asked some questions including the following. He asked, ‘Tell me about sleeping. How many kinds of sleeping are there?’ He (MGB) replied, “There are four kinds of sleeping: the sleeping of the Prophets who sleep on their backs; the sleeping of the faithful believers who sleep on their right sides; the sleeping of the rulers and their offspring who sleep on their left sides so that they may digest all that they have eaten; and the sleeping of Satan, his brethren, and the insane ones who sleep on their stomachs.”